diff --git a/homeassistant_api/_async/asyncclient.py b/homeassistant_api/_async/asyncclient.py
index 452d9507..ca5d8182 100644
--- a/homeassistant_api/_async/asyncclient.py
+++ b/homeassistant_api/_async/asyncclient.py
@@ -197,7 +197,7 @@ async def async_trigger_service(
     ) -> List[State]:
         """Tells Home Assistant to trigger a service, returns stats changed while being called"""
         data = await self.async_request(
-            join("services", domain + "/" + service),
+            f"services/{domain}/{service}",
             method="POST",
             json=service_data,
         )
diff --git a/homeassistant_api/rawapi.py b/homeassistant_api/rawapi.py
index 68f707f5..688cbb0b 100644
--- a/homeassistant_api/rawapi.py
+++ b/homeassistant_api/rawapi.py
@@ -1,9 +1,9 @@
 """Module for parent RawWrapper class"""
 
-import os
 import re
 from datetime import datetime
 from typing import Dict, Optional, Tuple, Union
+from urllib.parse import urljoin as join
 
 from .const import DATE_FMT
 from .models import Entity
@@ -42,7 +42,7 @@ def __init__(
 
     def endpoint(self, path: str) -> str:
         """Joins the api base url with a local path to an absolute url"""
-        return os.path.join(self.api_url, path)
+        return join(self.api_url, path)
 
     @property
     def _headers(self) -> Dict[str, str]:
@@ -122,7 +122,7 @@ def prepare_get_entity_histories_params(
         if start_timestamp is not None:
             if isinstance(start_timestamp, datetime):
                 formatted_timestamp = start_timestamp.strftime(DATE_FMT)
-                url = os.path.join("history/period", formatted_timestamp)
+                url = join("history/period", formatted_timestamp)
             else:
                 raise TypeError(f"timestamp needs to be of type {datetime!r}")
         else:
@@ -148,7 +148,7 @@ def prepare_get_logbook_entry_params(
         if start_timestamp is not None:
             if isinstance(start_timestamp, datetime):
                 formatted_timestamp = start_timestamp.strftime(DATE_FMT)
-            url = os.path.join("logbook", formatted_timestamp)
+            url = join("logbook", formatted_timestamp)
         else:
             url = "logbook"
         return params, url